Julia - bought - her sister - a bicycle. (For whom did she buy it? For her sister.)

Indirect objects are usually living beings like people or animals, but direct objects can be either people or things. If a verb has only one object, it will be a direct object.

Indirect objects usually come between the verb and the direct object. It is possible to restate these sentences using the proposition to and for. While we can still think of the word following the proposition as an indirect object, some grammarians would say that the indirect object has instead become the object of a preposition.